JP2003207863A - Image pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress costs for loading a reading light irradiation means and a driving means in an image pickup device provided with two solid-state detectors. <P>SOLUTION: In the image pickup device 1 consisting of a 1st solid-state detector 10, a 2nd solid-state detector 20, a 1st reading light irradiation means 100 for irradiating the first solid-state detector 10, a 2nd reading light irradiation means 110 for irradiating the 2nd solid-state detector 20 with reading light, a driving means 50, etc., the two reading light irradiation means 100, 110 are driven by a single driving means 50 in a scanning direction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus for simultaneously obtaining a plurality of radiation image data used for superposition processing by one shot method or energy subtraction processing by using a plurality of solid state detectors. Is.

[0002]

2. Description of the Related Art Conventionally, in medical X-ray photography,
In order to reduce the exposure dose to the subject and to improve the diagnostic performance, a solid state detector (electrostatic recording) is used for a photoconductor such as a selenium plate made of a-Se (amorphous selenium), which is sensitive to radiation such as X-rays. As a body), the solid-state detector is irradiated with recording radiation (recording light) such as X-rays carrying the radiation image information so that latent image charges carrying the radiation image information are stored in the electricity storage unit of the solid-state detector. By accumulating and then scanning the solid-state detector with electromagnetic waves (reading light) for reading such as laser beam, the current generated in the solid-state detector is detected through the flat plate electrodes or stripe electrodes on both sides of the solid-state detector. , A system for reading an electrostatic latent image carried by a latent image charge, that is, a radiation image information is known (for example,
JP-A-2000-105297, 2000-2840
No. 56).

On the other hand, conventionally, in recording and reading a radiation image using a stimulable phosphor sheet or the like, two or more sheets are superposed, and the radiation transmitted through the subject is radiated on each sheet, and each sheet is irradiated. A so-called superposition process is known in which noise in the radiographic image is reduced by superimposing (adding) each signal after appropriately weighting the image signal obtained by reading the radiographic image stored and recorded in (For example, JP-A-56-11399, JP-A-3-109679, and patent registration 2627.
086).

Further, by utilizing the fact that a specific structure of a subject (eg, organ, bone, blood vessel, etc.) has a characteristic of absorbing radiation energy, two radiation images recorded with different energy distributions are used. A so-called energy subtraction process is known, in which each image signal is appropriately weighted and then subtraction (subtraction) is performed between both signals to obtain a radiation image in which only a specific subject part in the radiation image is emphasized or extracted. (For example, JP-A-59-83486 and JP-A-60-225541.
Japanese Patent Laid-Open No. 3-109679, Japanese Patent Registration No. 26
27086).

In the subtraction process, as described in, for example, Japanese Patent Application Laid-Open No. 60-225541, a plurality of radiographs are carried out using radiations having different energies, and a plurality of the resulting images are obtained. Of a plurality of shots (two shots in the case of two times) for performing subtraction processing on the basis of an image signal obtained by reading a radiation image of the above-mentioned Japanese Patent Laid-Open No. 59-83486. By irradiating a plurality of (for example, two) recording sheets with the radiation that has passed through the subject, the radiation images carrying the high-energy component and the low-energy component of the radiation can be simultaneously recorded on each sheet in one shooting. There is a one-shot method for storing and recording.

In the multi-shot method, since there is a time lag between a plurality of times of photographing, the subject moves during that time, and a visible image reproduced based on the image signal after the subtraction processing causes a plurality of images due to this movement. There is a problem in that a false image (motion artifact) is generated due to a mismatch between the images, and the quality of the visible image is significantly deteriorated. On the other hand, the one-shot method is a method of capturing a plurality of images at the same time, and thus has an advantage that a false image due to the movement of the subject does not occur.

Further, the applicant of the present application has proposed a solid-state radiation detector suitable for performing the above-mentioned superposition processing and energy subtraction processing using the one-shot method in recording and reading of a radiation image using the solid-state radiation detector. It has been proposed (Japanese Patent Laid-Open No. 7-84056).

This detector is formed by laminating a plurality of radiation solid state detectors (radiation detecting layers), and further laminating a filter made of a substance absorbing a low energy component of radiation so as to be suitable for subtraction processing. I also suggest what I did.

[0009]

By the way, in the image pickup apparatus incorporating the solid-state detector used in the above-mentioned one-shot method, the reading light irradiating means and the reading light irradiating means are provided in order to read the electrostatic latent images from the two solid-state detectors. Since two sets of driving means for driving the reading light irradiating means are required, the normal 1
The cost for the reading light irradiating means and the driving means is higher than that of the image pickup apparatus having one solid-state detector.

In view of the above circumstances, the present invention has an object to provide an image pickup device having two solid-state detectors, in which the cost for mounting the reading light irradiation means and the driving means is suppressed. It is what

[0011]

A first image pickup device according to the present invention records image information as an electrostatic latent image by being irradiated with recording light carrying image information, and scans with the reading light. First to generate a current according to the electrostatic latent image by
The solid-state detector and the second solid-state detector, wherein the first solid-state detector and the second solid-state detector are provided in parallel with each other at a predetermined interval, facing each other. A first reading light irradiating means for irradiating a reading light incident surface of the first solid state detector with a linear reading light, and a second for irradiating a reading light incident surface of the second solid state detector with a linear reading light. The reading light irradiating means, the first reading light irradiating means, and the second reading light irradiating means are driven together in a direction substantially orthogonal to the linear direction of the reading light.
And two driving means.

Further, the second image pickup device according to the present invention records the image information as an electrostatic latent image by irradiating the recording light carrying the image information, and scans with the reading light to form the electrostatic latent image. A first solid-state detector and a second solid-state detector that generate a current according to an image are provided, and the first solid-state detector and the second solid-state detector are incident on the reading light of the first solid-state detector. In the image pickup device in which the surface and the reading light incident surface of the second solid-state detector face each other and are provided in parallel at a predetermined interval, one light source for generating the reading light and the reading light A reading light irradiation unit having an optical system for linearly irradiating the reading light incident surfaces of the first solid state detector and the second solid state detector simultaneously, and the reading light irradiating unit in a linear direction of the reading light. Drive means for driving in a substantially orthogonal direction.

In the above first and second image pickup devices, it is preferable that an energy separation filter is provided between the first solid state detector and the second solid state detector when the recording light is irradiated.

In the first and second image pickup devices, the "solid-state detector" is an electrostatic latent image of the image information carried by the recording light when the recording light such as light or radiation is irradiated. Is recorded and scanned by the reading light,
Any device may be used as long as it can generate a current according to the electrostatic latent image, for example, the above-mentioned Japanese Patent Laid-Open No. 2000-10.
The electrostatic recording material described in Japanese Patent No. 5297 can be used.

[0015]

According to the first image pickup apparatus of the present invention, the two reading light irradiating means provided for the two solid state detectors are driven by one driving means. The cost for the reading light irradiating means and the driving means can be suppressed more than when two sets of driving means are provided.

Further, in the second image pickup device of the present invention, the reading light irradiating means is one light source for generating the reading light, and the reading light is read by the first solid state detector and the second solid state detector. An optical system for simultaneously linearly irradiating the light incident surface is provided, and the one reading light irradiating means provided for the two solid state detectors is driven by one driving means. Further, the cost for the reading light irradiation means and the driving means can be further suppressed as compared with the first image pickup device.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an image pickup device according to a first embodiment of the present invention.

The image pickup device 1 according to the present embodiment has a first solid-state detector 10 formed on a glass substrate 5, a second solid-state detector 20 formed on a glass substrate 6, and a first solid-state detector 20. Energy separation filter 60 provided between the solid state detector 10 and the second solid state detector 20, a first current detecting means 70 connected to the first solid state detector 10, and a second current detecting means 70.
Second current detecting means 80 connected to the solid-state detector 20 of
A recording light irradiation means 90, a first reading light irradiation means 100 for irradiating the first solid state detector 10 with the reading light, and a second reading light for irradiating the second solid state detector 20 with the reading light. Irradiation means 110, drive means 50 for driving the first reading light irradiation means 100 and the second reading light irradiation means 110, and the second
Size correction means 30 connected to the current detection means 80
And the first current detecting means 70 and the size correcting means 30.
And an image processing means 40 connected to the.

This image pickup device 1 is provided with two solid state detectors, and with respect to the image signals obtained from the first solid state detector 10 and the second solid state detector 20 by one photographing. It is possible to perform a subtraction process, an overlay process, and the like, which will be described later.

FIG. 2 is a diagram showing a schematic configuration of the solid-state detector used in this embodiment. 2A is a perspective view, FIG. 2B is an XZ sectional view of the Q arrow finger portion, and FIG. 2C is an XY sectional view of the P arrow finger portion.

The first solid-state detector 10 irradiates a first conductive layer 11 that transmits radiation L1 such as recording X-rays (hereinafter referred to as recording light), and recording light L1 that passes through the first conductive layer 11. Photoconductive layer for recording 1 which exhibits conductivity when exposed to light
2. Acts as a substantially insulator against latent image charges (eg, negative charges), and as a substantially conductor against transport charges having the opposite polarity to the latent image charges (positive charges in the above example). The charge transport layer 13 that acts, the reading photoconductive layer 14 that exhibits conductivity by being irradiated with the reading electromagnetic wave (hereinafter referred to as reading light) L2, and the second conductive layer 15 that transmits the reading light L2.
Are laminated in this order. The first solid-state detector 10 is formed in order from the second conductive layer 15 on the support 5 that transmits the recording light L1 and the reading light L2, but the support 5 is not shown.

The material of the recording photoconductive layer 12 is
Rufus selenium (a-Se), PbO, PbI_TwoEtc.
Lead (II) oxide, lead (II) iodide, Bi₁₂(Ge, S
i) O ₂₀, Bi_TwoI_Three/ Organic polymer nanocomposite
Photoconductive material containing at least one of
Is appropriate.

The material of the charge transport layer 13 is, for example,
1 Mobility of negative charge charged in the conductive layer 11 and its opposite polarity
The larger the difference in the mobility of positive charges, the better (for example, 1
0^Two Above, preferably 10^ThreeOr more) Poly N-vinyl chloride
Lubazole (PVK), N, N'-diphenyl-N, N'-bis
(3-Methylphenyl)-[1,1'-biphenyl] -4,4 '
-Organic such as diamine (TPD) and discotic liquid crystal
Compounds or TPD polymers (polycarbonate
G, polystyrene, PUK) dispersion, Cl 10-20
A semiconductor material such as 0 ppm doped a-Se is suitable.
It In particular, organic compounds (PVK, TPD, discote
Liquid crystal) is preferable because it has a light insensitivity.
In addition, since the dielectric constant is generally small, the charge transport layer 13 and the reading
The capacitance of the photoconductive layer 14 becomes small, and the signal is taken out at the time of reading.
The efficiency can be increased. In addition, "There is light insensitivity
"Yes" means that even if the recording light L1 or the reading light L2 is irradiated.
It means that it hardly exhibits conductivity.

The material of the reading photoconductive layer 14 is a-
Se, Se-Te, Se-As-Te, metal-free phthalocyanine, metal phthalocyanine, MgPc (Magnesium ph)
talocyanine), VoPc (phaseII of Vanadyl phthal
Cyanine), CuPc (Cupper phtalocyanine), or the like, and a photoconductive substance containing at least one of them as a main component is suitable.

The thickness of the recording photoconductive layer 12 is equal to the recording light L1.
In order to be able to absorb
It is preferably not more than 00 μm, and in this example, about 5 μm.
It is set to 00 μm. In addition, the charge transport layer 13 and the photoconductive layer 1
4 and the total thickness is 1/2 of the thickness of the recording photoconductive layer 12.
It is desirable that the thickness be less than or equal to 1 and the thinner the thickness, the better the response at the time of reading. Therefore, it is preferably 1/10 or less, more preferably 1/20 or less.

The first conductive layer 11 may be any material that is transparent to the recording light L1. For example, when visible light is used as the recording light, a Nesa film (known as a light-transmitting metal thin film) ( _{SnO 2), ITO (Indium Tin} Oxi
de) or IDIXO (Idemitsu Indium X-me), which is an amorphous light-transmissive metal oxide that is easy to etch
tal Oxide; Idemitsu Kosan Co., Ltd. and other metal oxides 50 to 2
It can be used with a thickness of about 00 nm, preferably 100 nm or more. In addition, pure metal such as aluminum Al, gold Au, molybdenum Mo, and chromium Cr is used, for example, 20n.
Although it is possible to make visible light transmissive by making the thickness m or less (preferably about 10 nm), in the present embodiment, X-rays are used as the recording light L1 and the first conductive layer is used. Since an image is recorded by irradiating the X-ray from the 11 side, the first conductive layer 11 does not need to have visible light transparency.
It is also possible to use a pure metal such as Al or Au having a thickness of 0 nm. In this embodiment, the first conductive layer 11 is made of Au with a thickness of 100 nm.

The electrode of the second conductive layer 15 is formed as a stripe electrode 16 in which a large number of elements (linear electrodes) 16a are arranged in a stripe shape. Here, the material of the electrode material forming the stripe electrode 16 is ITO.
(Indium Tin Oxide), IDIXO (Idemitsu Indium
X-metal Oxide; Idemitsu Kosan Co., Ltd., aluminum, molybdenum, or the like can be used. Element 16
The space 15a between a may be filled with a polymer material such as polyethylene in which a small amount of a pigment such as carbon black is dispersed, and may have a property of blocking the reading light L2.

Since the second solid-state detector 20 used in this embodiment has the same structure as the first solid-state detector 10, the drawing and description thereof are omitted. (The elements that make up the second solid-state detector 20 are the same as the elements that make up the first solid-state detector 10, and the elements that make up the second solid-state detector 20 are the elements that make up the first solid-state detector 10. It is assumed that 10 is added to the number of each constituent element.)
The energy separation filter 60 uses the first solid-state detector 10 in order to perform the energy subtraction process described later.
It is for absorbing the low energy component of the radiation that has passed through, and specifically Cu or the like is used.

A specific example of the first reading light irradiating means 100 will be shown in FIG. 3 and its structure and operation will be described. Figure 3
FIG. 3A is a side view showing the detailed configuration of the first reading light irradiation means 100 shown in FIG. 1 as seen from the Y direction, and FIG.
(B) is an XY sectional view of the first reading light irradiation means 100.

As shown in FIG. 3, the first reading light irradiation means 100 includes a plurality of LEs arranged linearly in the Z-axis direction.
A light source 101 including D chips 101a, 101b, ...
And an opening 102a extending in the longitudinal direction of the light source 101 for improving the quality of light emitted from the light source 101.
And a first optical means 106 composed of a cylindrical lens 104, 105 which is an optical member 103 for converging the light toward an opening 102a of the slit 102 and a light source which has passed through the first optical means 106. A cylindrical lens 107 for focusing on the surface of the solid-state detector in a direction orthogonal to the longitudinal direction of 101;
And a second optical means 109 composed of 108.

The slit 102 spatially filters the light output from the light source to suppress flare light, and determines the beam diameter on the detector. Note that the slit may be any slit as long as it suppresses the spatial spread of light, and may be not only a mechanical slit having an opening as in the present embodiment but also an optical gap such as a concentration distribution filter. .

Light emitted from each light emitting point of the light source 101, that is, each LED chip 101a, 101b, ... Is slit 102 by cylindrical lenses 104 and 105.
Is focused and filtered in the longitudinal direction of the aperture 102a of the second optical means 109, is focused in the direction orthogonal to the longitudinal direction of the light source by the cylindrical lenses 107 and 108 of the second optical means 109, and is irradiated onto the first solid-state detector 10. It Since the light beam from each LED chip spreads isotropically and diffuses and is not focused in the longitudinal direction of the light source, the light from each chip diffuses in the longitudinal direction of the light source on the detector. As a result, the light from the light source 101 irradiates the first solid-state detector 10 linearly, and the light from each chip simultaneously exposes a plurality of pixels lined up linearly. That is, each pixel on the first solid-state detector 10 is simultaneously exposed by the light output from the plurality of LED chips. For example, FIG. 3 is a schematic diagram showing the first
Point A on the solid-state detector 10 is exposed by seven LED chips at the same time.

More specifically, for example, the focal length of the optical system is 40 mm, the pixel size is 100 μm, the LED chip interval (light emitting point interval) is 200 μm, and the beam divergence angle from the LED chip in the longitudinal direction of the light source is 120 °. (Half), each pixel on the detector is simultaneously exposed to light from at least 700 or more LED chips.

The above-mentioned first reading light irradiation means 100 is used.
In, in place of the cylindrical lenses 104 and 105 of the first optical means 106, SELFOC lenses may be used. Further, the light source 101 of the first reading light irradiation means 100 described above is configured by arranging a plurality of LED chips, but it may be configured by arranging a plurality of LD chips instead of the LED chips. Further, an LED array or an LD array in which a plurality of light emitting points are arranged in a line may be used as a light source.

Further, the second reading light irradiating means 110 used in the present embodiment has the same structure as the first reading light irradiating means 100, and therefore the drawing and description thereof are omitted. (The elements constituting the second reading light irradiating means 110 are the same as the elements constituting the first reading light irradiating means 100, and each element constituting the second reading light irradiating means 110 is the first reading light. It is assumed that 10 is added to the number of each element constituting the irradiation means 100.) A specific example of the driving means 50 will be shown in FIG. FIG. 4 is a diagram showing a schematic configuration of the driving means 50 shown in FIG.

The driving means 50 is the first reading light irradiation means 1
00 and the second reading light irradiation means 110 in the scanning direction, and the DC motor 5 as a driving device.
0b and a ball screw 50c in combination, and a control means 50a for controlling them. The first read light irradiation means 100 and the second read light irradiation means 110 are mechanically connected by a connecting member 50d, and this connecting member 50d is combined with the ball screw 50c. Therefore, by driving the DC motor 50b by the control means 50a and rotating the ball screw 50c, the first reading light irradiating means 100 and the second reading light irradiating means 110 fixed to the coupling member 50d.
Can be simultaneously driven in the scanning direction.

The drive device may be any drive device other than the above, as long as it can be driven in a linear direction, and for example, a linear motor or the like may be used.

A specific example of the first current detecting means 70 will be shown in FIG. 5 and its configuration and operation will be described. FIG. 5 shows the X of the first solid-state detector 10 used in the image pickup device according to the present invention.
It is a figure showing the details of the 1st electric current detection means 70 with a Z section view.

The first current detecting means 70 obtains an image signal of a level corresponding to the amount of latent image charge accumulated in the electricity storage section 19, and each element 16 of the stripe electrode 16 is provided.
It has a large number of current detection amplifiers 71 connected for each a. The current detection amplifier 71 includes an operational amplifier 71a, an integrating capacitor 71b and a switch 71c. The first conductive layer 11 of the first solid-state detector 10 is connected to one of the switches 73 and the negative electrode of the power supply 72. The positive electrode of the power supply 72 is connected to the other of the switches 73. The non-inverting input terminal (+) of each operational amplifier 71a is commonly connected to one end of the switch 73, and the inverting input terminal (−) is the element 1
6a are individually connected.

The switch 73 is connected to the power supply 72 side at the time of recording, and a predetermined DC voltage from the power supply 72 is applied between the first conductive layer 11 and the stripe electrode 16 through an imaginary short circuit of an operational amplifier. .

On the other hand, at the time of reading, the switch 73 is connected to the side of the first conductive layer 11 and the first electrode layer and the stripe electrode 16 are short-circuited through the immergenary short circuit of the operational amplifier to read a line shape. By exposing the stripe electrode 16 to the light L2, each current detection amplifier 7
1 simultaneously detects the current flowing through each element 16a for each connected element 16a. The configuration of the first current detection means 70 and the current detection amplifier 71 is as follows.
The present invention is not limited to this example, and various types can be used.

Regarding the second current detecting means 80 used in this embodiment, the first current detecting means 7 is used.
Since it has the same configuration as 0, the drawing and description are omitted. (The elements forming the second current detecting means 80 are the same as the elements forming the first current detecting means 70, and the elements forming the second current detecting means 80 are the same as the elements forming the first current detecting means 70. It is assumed that 10 is added to the number of each constituent element.) Here, image information is recorded as an electrostatic latent image on the solid-state detector used in the image pickup apparatus of the present embodiment, and the recorded electrostatic image is recorded. A method of reading the latent image will be described.

Although the electrostatic latent image recording / reading process for the first solid-state detector 10 will be described in the present description, the same applies to the second solid-state detector 20.

A subject 9 is provided on the upper surface of the first conductive layer 11, and the subject 9 has a portion 9 for transmitting the recording light L1.
There is a blocking portion (light blocking portion) 9b that does not pass through a. The recording light irradiation means 90 uniformly irradiates the subject 9 with the recording light L1.

The reading light irradiating means 100 applies the reading light L2, which is substantially uniform in a line shape orthogonal to the scanning direction, to the stripe electrode 1.
6 is used for scanning exposure in the longitudinal direction (scanning direction) of each element 16a. In this scanning exposure, continuous light may be emitted or pulsed light may be emitted.

First, the electrostatic latent image recording process will be described with reference to the charge model shown in FIG. The recording light L
Negative charges and positive charges generated in the recording photoconductive layer 12 by 1 are represented by circles-or + in the drawing. Further, the glass substrate 5 of the first solid-state detector 10 is not shown.

When recording an electrostatic latent image on the first solid-state detector 10, first, the switch 73 is switched to the power source 72 side,
A DC voltage is applied between the first conductive layer 11 and the stripe electrode 16 to charge them. As a result, a substantially U-shaped electric field is formed between the first conductive layer 11 and the stripe electrode 16, and almost all of the recording photoconductive layer 12 has a substantially parallel electric field. Conductive layer 12 and charge transport layer 13
There is a portion where there is no electric field at the interface with and, that is, in the electricity storage unit 19. Then, an electric field distribution in which the U-shaped electric field is continuous in the length direction of the element 16a is formed (FIG. 6A).

Next, radiation (recording light L1) is bombarded onto the subject 9, and the recording light L1 carrying the radiation image information of the subject 9 which has passed through the transmitting portion 9a of the subject 9 is applied to the first solid-state detector 1.
Irradiate to 0. Then, positive and negative charge pairs are generated in the recording photoconductive layer 12 of the first solid-state detector 10, and the negative charges therein move to the power storage unit 19 along the above-described electric field distribution (FIG. )). On the other hand, the positive charges generated in the recording photoconductive layer 12 move toward the first conductive layer 11 at high speed, and are injected from the power source 72 at the interface between the first conductive layer 11 and the recording photoconductive layer 12. Negative charge and charge recombine and disappear. Further, since the recording light L1 does not pass through the light blocking portion 9b of the subject 9, the first light
The portion of the solid-state detector 10 corresponding to the lower portion of the light-shielding portion 9b does not change at all (FIGS. 6B and 6C).

In this way, by irradiating the subject 9 with the recording light L1, charges corresponding to the subject image are stored in the electricity storage unit 19 which is an interface between the recording photoconductive layer 12 and the charge transfer layer 13.
Will be able to accumulate in. The amount of the accumulated latent image charge (negative charge) is substantially proportional to the dose of the radiation that has passed through the subject 9 and is incident on the first solid-state detector 10. Therefore, the latent image charge carries an electrostatic latent image. As a result, the electrostatic latent image is recorded on the first solid-state detector 10.

When the electrostatic latent image is read from the first solid-state detector 10, the switch 73 is first set to the first conductive layer 11 side, and the first conductive layer 11 and the stripe electrode 16 are imaginarily shorted to the operational amplifier 71a. Short circuit through to rearrange the charge. Next, by scanning the first reading light irradiation means 100 in the longitudinal direction (scanning direction) of the element 16a, the first solid state detector 10 is exposed by scanning with the linear reading light L2. The scanning exposure of the reading light L2 causes the reading light L2 corresponding to the scanning position to enter the photoconductive layer 14.
Positive and negative charge pairs are generated inside.

A very strong electric field (strong electric field) is formed between the electricity storage unit 19 and the stripe electrode 16, and the charge transport layer 13 acts as a conductor for positive charges. Therefore, the positive charge generated in the reading photoconductive layer 14 rapidly moves in the charge transport layer 13 so as to be attracted to the latent image charge in the storage portion 19, and the latent image charge and charge recombination is performed in the power storage portion 19. Then disappears. On the other hand, the photoconductive layer 1 for reading
The negative charges generated in No. 4 are the first conductive layer 11 and the stripe electrode 1.
The positive charges of 6 are recombined with each other and disappear. A voltage change between the first conductive layer 11 and the stripe electrode 16 due to the charge recombination is detected as a current change by the current detection amplifier 71. The current flowing through the first solid-state detector 10 at the time of this reading corresponds to the latent image charge, that is, the electrostatic latent image. Therefore, by detecting this current by the current detection amplifier 71, the electrostatic latent image is detected. An image can be read, ie an image signal representative of the electrostatic latent image can be acquired.

The size correction means 30 is connected to the second current detection means 80, performs reduction correction calculation on the image signal S20 detected by the second current detection means 80, and
The sizes of the images detected by the current detecting means 70 and 80 are made the same.

The image processing means 40 is connected to the output portions of the current detecting means 70 and the size correcting means 30. In addition,
Although not shown, the image processing means 40 is connected to a reproducing means for outputting a radiation image of a subject as a visible image. As the reproducing means, an electronic display such as a CRT,
Various devices such as a device that records a radiation image displayed on a CRT or the like on a video printer or the like can be adopted.

The operation of the image pickup apparatus 1 will be described below with reference to FIG.

After forming a predetermined electric field on the first solid-state detector 10 and the second solid-state detector 20, the recording light irradiation means 9 is formed.
The subject 9 is irradiated with radiation (recording light L1) from 0. The recording light L1 transmitted through the subject 9 is incident on the first solid-state detector 10, and a latent image charge corresponding to the intensity of the recording light L1 incident on the first solid-state detector 10 is accumulated in the power storage unit 19. On the other hand, of the recording light L1 radiated to the first solid-state detector 10, the recording light L1 not absorbed in the first solid-state detector 10 passes through the energy separation filter 60 and is detected as the second solid-state detection. A latent image charge corresponding to the intensity of the recording light L1 that has entered the container 20 and has entered the second solid-state detector 20 is accumulated in the power storage unit 29.

After the electrostatic latent image is recorded as described above, the first reading light irradiating means 100 and the second reading light irradiating means 110 are driven by the driving means 50 in the scanning direction (the linear electrode 16).
a, 26a longitudinal direction), the first solid-state detector 1
0 and the second solid-state detector 20 are respectively scanned by the linear reading light L2, so that currents corresponding to latent image charges are generated from the first solid-state detector 10 and the second solid-state detector 20. Is output.

The currents output from the first solid state detector 10 and the second solid state detector 20 are detected by the first current detecting means 70 and the second current detecting means 80.

Of the image signal S10 detected by the first current detecting means 70 and the image signal S20 detected by the second current detecting means 80, the image signal S20 is input to the size correcting means 30 and the corrected image is obtained. A size correction calculation is performed so that the sizes of the images carried by the signal S20 ′ and the image signal S10 are the same.

Here, the correction calculation of the image size of the image signal S20 'in the present embodiment will be described. As shown in FIG. 1, the distance from the recording light irradiation means 90 to the first solid-state detector 10, that is, FID (Focus Image Di
stance) is f and the distance from the first solid-state detector 10 to the second solid-state detector 20 is t, with respect to the size of the image detected by the front-side first solid-state detector 10,
The magnification α of the image size detected by the second solid-state detector 20 on the rear side is expressed as α = (f + t) / f 2 (1), and the closer to the periphery of the solid-state detector, The gap between the front and back images becomes large.

Then, the magnification α is obtained by inputting f and t to the size correcting means 30 from a keyboard (not shown), and the size of the image represented by the image signal S20 is multiplied by 1 / α, that is, the image signal S20 represents. Image size is f
The size of the image is corrected by the reduction correction calculation for obtaining the image signal S20 ′ representing the image multiplied by / (f + t). When f and t are constants, it is not necessary to input them with a keyboard or the like. In addition, as a method of matching the sizes of the images represented by the image signals S10 and S20, any method other than the above may be used.

The image size correction calculation is performed as described above, and after the images represented by the image signal S10 and the image signal S20 'have the same size, two image signals S1 are generated.
0, S20 ', subtraction processing, that is, S = Wa * S10-Wb * S20' + C (2) where Wa and Wb are weighting coefficients, and C is weighted subtraction according to the bias component. , This allows
An image signal S corresponding to the image of the difference between the two images is generated. The image signal S is sent to a reproducing means (not shown), and a visible image (energy subtraction image) based on the image signal S is displayed and output on the reproducing means.

In the above embodiment, the image processing means 40 performs the energy subtraction processing. However, when performing the superposition processing, the image processing means 40 is provided between the first solid state detector 10 and the second solid state detector 20. Since the energy separation filter 60 is not provided and the calculation by the image processing means 40 is added instead of subtraction, the detailed description of the superposition processing will be omitted.

According to the image pickup apparatus of this embodiment, 2
Since the two reading light irradiating means are driven by one driving means for one solid state detector, the cost for the reading light irradiating means and the driving means is lower than that of providing two pairs of the reading light irradiating means and the driving means. Can be suppressed.

In the image pickup apparatus of this embodiment, which surface of the first solid state detector and the second solid state detector face each other depends on the apparatus configuration such as the arrangement of the reading light irradiation means. And set appropriately.

Next, a second embodiment of the present invention will be described with reference to FIG. In addition, in FIG.
Elements that are the same as the elements inside are given the same numbers, and descriptions thereof are omitted unless otherwise necessary.

In the image pickup device 2 of the present embodiment, the read light L2 incident surface of the first solid state detector 10 and the read light L2 incident surface of the second solid state detector 20 are arranged so as to face each other, By the one reading light irradiating means 120 which irradiates the reading light in two directions, the first solid-state detector 10 and the second solid-state detector 2 are provided.
It is different from the first embodiment in that 0 scanning is performed.

A specific example of the reading light irradiation means 120 will be shown in FIG. 8 and its configuration will be described. As shown in FIG. 8A, in this reading light irradiation means 120, the two reading light irradiation means used in the first embodiment are combined so that the emission directions of the reading light are substantially opposite to each other. It is a thing.

In the mode shown in FIG. 8A, the two reading light irradiating means are driven by one driving means.
Compared with the mode shown in (2), since the two reading light irradiating means are adjacent to and integrated with each other, the structure of the driving means can be simplified.

Further, the reading light irradiation means is shown in FIG. 8 (B).
The embodiment shown in FIG. This reading light irradiation means 140
Is composed of a plurality of LED chips 141a, 141b, ... Arranged linearly in the Z-axis direction, one light source 141 emitting light in a direction substantially parallel to the solid-state detector, and the light source 14
1. Cylindrical lens 144 that makes the light emitted from 1 substantially parallel, and splits the light that has passed through the cylindrical lens 144 into two directions, a direction orthogonal to the first solid-state detector 10 and a direction substantially parallel to the solid-state detector. Beam splitter 160, a cylindrical lens 145 that collects light emitted from the beam splitter 160 in a direction orthogonal to the first solid-state detector 10, and a quality of light emitted from the light source 141. A slit 142 having an opening 142a extending in the longitudinal direction of the light source 141, and an optical means 149 for focusing the light passing through the slit 142 on the surface of the first solid-state detector 10 in the direction orthogonal to the longitudinal direction of the light source 141. , The light emitted from the beam splitter 160 in a direction substantially parallel to the solid-state detector is orthogonal to the second solid-state detector 20. A mirror 161 that reflects in the direction, a cylindrical lens 155 that collects the light reflected by the mirror 161, and an opening 152a that extends in the longitudinal direction of the light source 141 to improve the quality of the light emitted from the light source 141. The slit 152 having the slit 152
And an optical means 159 for converging the light that has passed through the second solid-state detector 20 in the direction orthogonal to the longitudinal direction of the light source 141.

In the embodiment shown in FIG. 8B, the reading light irradiating means is composed of one light source and an optical system which divides the light emitted from this light source into two directions.
Similar to the mode shown in (A), the structure of the driving means can be simplified as compared with the mode shown in FIG.

In addition to the above, any reading light irradiating means for irradiating the reading light in two directions may be used.

By the way, in order to obtain an image for performing the above subtraction processing, an energy separation filter 60 is provided between the first solid-state detector 10 and the second solid-state detector 20 at the time of irradiation of the recording light. Although it is necessary, since the energy separation filter 60 is generally impermeable to the reading light, in the present embodiment, it becomes impossible to irradiate the reading light to any of the solid state detectors at the time of irradiating the reading light. Therefore, the energy separation filter 60 is provided in the first solid state detector 10 and the second solid state detector 2 only when the recording light is irradiated.
Since it may be between 0 and 0, the energy separation filter 60 may be manually pulled out or mechanically moved during irradiation of the reading light.

Instead of moving the energy separation filter 60, an energy absorbing substance (reading light transmissive) is mixed in the glass substrate 5 and / or the glass substrate 6, or an energy separating filter permeable to reading light is used. You may use.

According to the image pickup apparatus of this embodiment, 2
Since one reading light irradiating means is driven by one driving means for one solid-state detector, the cost for the reading light irradiating means and the driving means is further increased as compared with the image pickup apparatus according to the first embodiment. Can be suppressed.

Although the preferred embodiments of the image pickup apparatus according to the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without changing the gist of the invention. It is possible.

For example, in the present invention, since the reading light irradiation means is provided between the two solid state detectors, the distance t between the two solid state detectors becomes long. However, as the distance t between the two solid-state detectors becomes longer, when the sizes of the images represented by the image signals detected by the two solid-state detectors are matched, the solid-state detectors arranged on the rear surface are detected. The image represented by the image signal has a smaller image area. Therefore, when the recording light is irradiated, the reading light irradiation means is retracted from between the solid-state detectors, and one or both of the two solid-state detectors are mechanically moved so that the distance between the two solid-state detectors is increased when the recording light is irradiated. You may make it shorten t.

In each of the solid-state detectors used in the image pickup apparatus according to the above-mentioned embodiments, the recording photoconductive layer exhibits conductivity by irradiation with recording radiation. The recording photoconductive layer of the detector is not necessarily limited to this, and the recording photoconductive layer may exhibit conductivity by irradiation with light emitted by excitation of recording radiation (Patent Document 1) 2000-105
297). In this case, a wavelength conversion layer called a so-called X-ray scintillator that converts the wavelength of the recording radiation into light of another wavelength region such as blue light may be laminated on the surface of the first conductive layer. As the wavelength conversion layer, it is preferable to use, for example, cesium iodide (CsI) or the like. The first conductive layer is transparent to the light emitted from the wavelength conversion layer due to the excitation of the recording radiation.

Further, in the solid-state detector used in the image pickup device according to the above-mentioned embodiment, the charge transport layer is provided between the recording photoconductive layer and the reading photoconductive layer, and the charge transport layer and the recording photoconductive layer are provided. Although the power storage unit is formed at the interface with the layer, the charge transport layer may be replaced with a trap layer. When the trap layer is used, the latent image charge is captured by the trap layer, and the latent image charge is accumulated in the trap layer or at the interface between the trap layer and the recording photoconductive layer. Further, a microplate may be provided at the interface between the trap layer and the recording photoconductive layer for each pixel.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an image pickup apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view (A) of a solid-state detector used in the image capturing apparatus according to the first embodiment, an XZ sectional view of a Q arrow finger portion (B), and an XY sectional view of a P arrow finger portion (C).

FIG. 3 is a diagram showing a detailed configuration of a reading light irradiation unit used in the image pickup apparatus according to the first embodiment.

FIG. 4 is a diagram showing a schematic configuration of a drive unit used in the image pickup apparatus according to the first embodiment.

FIG. 5 is a diagram showing a schematic configuration of a current detection unit used in the image pickup apparatus according to the first embodiment.

FIG. 6 is a diagram illustrating a method of recording an electrostatic latent image on the solid-state detector.

FIG. 7 is a diagram showing a schematic configuration of an image pickup device according to a second embodiment of the present invention.

FIG. 8 is a diagram showing a detailed configuration of a reading light irradiation unit used in the image pickup apparatus according to the second embodiment.

[Explanation of symbols]

1 and 2 image pickup device 5, 6 glass substrate 10 First solid state detector 20 Second solid state detector 30 size correction means 50 driving means 60 energy separation filter 70 First Current Detection Means 80 Second current detection means 90 Recording light irradiation means 100 first reading light irradiation means 110 Second reading light irradiation means 120, 140 Read light irradiation means

Front page continued (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 5/32 H04N 5/335 Z 5/335 1/04 EF term (reference) 2G088 EE01 FF02 GG21 JJ05 JJ22 2H013 AC06 AC08 5C024 AX12 JX02 5C051 AA01 BA02 DA06 DB01 DB22 DB29 DC05 DC07 DE29 5C072 AA01 BA02 CA05 CA09 CA11 DA02 MA01 VA01

Claims (3)

[Claims] 1. A method for recording the image information as an electrostatic latent image by irradiating a recording light carrying image information, and generating a current according to the electrostatic latent image by scanning with the reading light. An image pickup device including a first solid-state detector and a second solid-state detector, wherein the first solid-state detector and the second solid-state detector are provided in parallel with each other with a predetermined gap therebetween. A first reading light irradiating means for irradiating a reading light incident surface of the first solid-state detector with a linear reading light; and a linear reading light for a reading light-incident surface of the second solid-state detector. Second reading light irradiating means for irradiating the reading light, and one driving means for driving the first reading light irradiating means and the second reading light irradiating means together in a direction substantially orthogonal to the linear direction of the reading light. An image pickup device comprising: 2. A recording light carrying image information is irradiated to record the image information as an electrostatic latent image, and scanning is performed with the reading light to generate a current corresponding to the electrostatic latent image. A first solid-state detector and a second solid-state detector, wherein the first solid-state detector and the second solid-state detector are the reading light incident surface of the first solid-state detector and the second solid-state detector. In an image pickup device provided in parallel with a reading light incident surface of a solid-state detector and at a predetermined interval, the light source for generating the reading light and the reading light for the first solid A reading light irradiating means having a detector and an optical system for irradiating the reading light incident surface of the second solid-state detector at the same time linearly; Drive means for driving in a direction substantially orthogonal to Image capturing device. 3. The image pickup device according to claim 1, wherein an energy separation filter is provided between the first solid-state detector and the second solid-state detector when the recording light is irradiated.